package moe.oko.Kiafumi.command;

import com.google.common.reflect.ClassPath;

import java.lang.reflect.Constructor;
import java.lang.reflect.InvocationTargetException;
import java.util.ArrayList;
import java.util.List;
import java.util.Set;
import java.util.stream.Collectors;

import static moe.oko.Kiafumi.Kiafumi.error;
import static moe.oko.Kiafumi.Kiafumi.info;

public class CommandRegistrar {

    public Set<Class> findAllClassesContaining(String packageName) {
        try {
            return ClassPath.from(ClassLoader.getSystemClassLoader())
                    .getAllClasses()
                    .stream()
                    .filter(clazz -> clazz.getPackageName()
                            .contains(packageName))
                    .map(clazz -> clazz.load())
                    .collect(Collectors.toSet());
        } catch (Exception ex) {
            error("Failed to load classes containing " + packageName + ", check stack.");
            ex.printStackTrace();
            return null;
        }
    }

    public List<CommandClass> getCommandClasses() {
        try {
            Set<Class> classes = findAllClassesContaining("moe.oko.Kiafumi.command");
            List<CommandClass> commands = new ArrayList<>();
            info("Found " + classes.size() + " classes containing moe.oko.Kiafumi.command in package class.");
            for (Class clazz : classes) {
                for (Constructor cnstr : clazz.getConstructors()) {
                    try {
                        var obj = cnstr.newInstance(); //making an attempt.
                        if (obj instanceof CommandClass) {
                            info("Instance found (" + cnstr.getName() + ")! Registering.");
                            commands.add((CommandClass) obj);
                        }
                    } catch (InstantiationException ex) {
                        //Ignore, this is just us trying to load the CommandClass abstract class. We ignore it.
                    }
                }
            }
            return commands;
        } catch (IllegalAccessException | InvocationTargetException exception) {
            //Now we don't ignore, this is a core issue.
            exception.printStackTrace();
            error("fucky wucky in class loading.");
            return null;
        }
    }
}